Hydrogen adsorption in ordered mesoporous carbon synthesized by a soft-template approach

An ordered mesoporous carbon was synthesized with soft-template approach as a potential adsorbent for hydrogen storage through physical adsorption. The carbon adsorbent prepared in this work has a Brunauer-Emmett-Teller (BET) specific surface area of 798 m²/g, uniform pore size distribution with an average pore diameter of 6.26 nm, and pore volume of 0.87 cm ³/g. Hydrogen adsorption equilibrium and kinetics in the carbon adsorbent were measured in a volumetric adsorption apparatus at 77,194.5, and 298 K. A hydrogen adsorption capacity of 1.27 wt % was observed at 1.05 bar and 77 K, hydrogen diffusivity in the carbon is estimated to be 1 × 10 ^-6 cm²/s at 194.5 K, and activation energy for hydrogen diffusion in the carbon is 0.236 kJ/mol. The isosteric heat of adsorption for hydrogen in the carbon adsorbent is between 3 and 6 kJ/mol, which is in the same range of the heat of adsorption of hydrogen measured on other carbonaceous materials.